Tuesday, November 29, 2011

Finally!!! Petrocosmeas are in the news and getting the attention we all knew they deserved! I was delighted by an article in the RHS publication "The Plantsman" back in September that announced a new name for one of our most popular Pet species...the former Petrocosmea rosettifolia. The new, and proper name for this plant is Petrocosmea cryptica as described and published by Julian Shaw of the RHS. I am attaching a link to the article here:www.rhs.org.uk/Plants/RHS-Publications/Journals/The-Plantsman/2011-Issues/September/Petrocosmea

Petrocosmea cryptica '#3' (formerly known as P. rosettifolia #3) shown above. There are several variants or clones of this species in cultivation. The one above has attractive leaf markings and large, pure white flowers with yellow throats.

Mr. Shaw finally did some of the much-needed taxonomic work on one of the more popular species in cultivation now for around ten years. In his article, Mr. Shaw mentions the fact that this species has been improperly labeled P. rosettifolia, and has also been distributed under various other names such as 'G25KC00' which I've discussed here in previous posts. In my collection, I've accumulated at least nine plants which I believe are simply different clones, likely from different collections, of this species. DNA analysis which we did with Niagara University, has shown that these various clones are all very closely related genetically, so close, in fact, that we believe they are all the same species. It is common from a species to contain individuals with quite different characteristics.

Pictured above is a plant in my collection which I call P. cryptica '#5 '(formerly labeled P. rosettifolia #5). This form has less distinct yellow veining in the leaves and lavendar flowers.

Pictured above is P. cryptica '#4' (formerly labeled P. rosettifolia '#4'). This form has white flowers and a distinct and vibrant yellow veining to the leaves. The flower form on this clone, to me, is less attractive than that of #3, but it tends to flower more heavily, and later than '#3'.

The photo above shows the variability in the foliage of P. cryptica clones in cultivation. This photo shows my plants of P. cryptica '#4' at the top and P. cryptica '#1' at the bottom. Two forms #1 and #2 both have leaves that are nearly totally green and more rounded in shape with smooth margins. Other clones show the distinct yellow veining and toothed leaf margins. Clones #1 and #2 also grow much more compact and have flowers in light lavendar to pink shades. DNA analysis, though, does show them to be the same species as the showier forms.

Mr. Shaw's article has lots of good information in it. And, it mentions this blog and three of my hybrids using P. cryptica - P. 'Rosemary Platz', P. 'Keystone's Bantam', and P. 'Keystone's Harvest Moon'. The first two are registered with the Gesneriad Society and show P. rosettifolia as the parent, since that was the name applied to the species at the time.

In the future, I hope to see more taxonomic work done on the many Pet species still being grown and distributed under names that are clearly incorrectly applied. P. minor and it's various forms being one in this group. P. sericea and sp.' HT-2' are also suspect in my opinion.

So, the question I am getting is "Should I change the labels on my plants?". I have changed my labels on the plants which I am reasonably certain fall under this newly published description. If I am in doubt, however, I say what I always say...keep the plant labeled as you acquired it, along with a notation of where and when you acquired it. One day, perhaps we will have the mess with Pet names sorted out. For the time being, though, enjoy growing the plants as they are.

I've missed blogging about my favorite plants। Sometimes, one is blessed with lots of "passions" in life, and priorities must shift. With only twenty-four hours in a day, and only one of me, the time left for plant passions is limited to only enough time for watering and maybe a little fertilizing and repotting. I'm happy to say, though, that at least for the moment, I'm finding a bit more time to not only water and fertilize, but also to stop and smell the Petrocosmeas (see my last post!!).

Most importantly, I must stop to say a most sincere "Thank you" to all of you who have taken the time to write, share photos, seek advice, and tell me of your experiences with Petrocosmea. It means a lot to hear that you have found the posts here on the blog helpful to your enjoyment of Pets. In the time that I have been away from the blog, I have continued, as time permitted, to do some experiments, study both old and new species, and to continue to grow and evaluate new seedlings for future release. I continue to learn so much about these plants every time I work with them. The feeding, watering and fertilizing may have been scarce, but my enthusiasm for the Pets remains. In your letters, you have given me many ideas for future posts, and I will do my best to get to those as soon as I can. Thank you for the suggestions, comments, and questions.

So, this morning, having a rare day off, I arose early and went to the basement to work with the plants. I was welcomed by the plant pictured above...Petrocosmea sericea, giving it's annual show of bloom. The plant pictured is now about ten years old. It was one of my earliest acquisitions as a gift of two leaves from a friend. This senior amoung my collection has been in the same pot for about four years now. It is potted in a 1:1:1 ratio mix of peat, perlite and vermiculite and is in a five inch pan pot. It sits on an acylic matting that is occasionally moistened for humidity. Humidity in my basement never gets below around 50% year round, and is often higher. This summer, as my work schedule has gotten busier, this plant has wilted several times and has only been fertilized maybe twice in the last year. But it is happy. This photo reasserts my advocacy of letting Pets dry out between waterings, and for going light on the fertilizer. One of the most common questions I get is "why won't my Pet bloom?" Often, with some questioning, I hear that the plants are kept constantly moist and fertilized often. It is true that his treatment makes lovely and lush foliage, but I fear it is at the expense of flowers. Pets in nature often grow in rather harsh conditions where they dry out between rains. Prior to taking the photo, I removed 17 spent flowers and there are 68 flowers still on the plant, if I counted them correctly. It makes a lovely sight and you can see the flower potential if given proper culture. SO, this morning, being greeted by this lovely sight, I took the time to stop and smell the Petrocosmeas! (I have three of these P. sericeas in bloom now.) And remember, this species is fragrant.... the scent is great! I hope you have some Pets in bloom to enjoy too~!!